he president of a university believes the entering class this year has an average ACT score different than previous years.  The average ACT score previously had been 23.  He took a sample of 100 students from this year’s entering class and found their sample mean ACT score is 24 with a sample standard deviation of 6.  Is there evidence the population mean ACT score is different from 23 at the 0.01 significance level? State the null and alternative hypotheses.

Charmaine recently switched her primary doctor to one specializing in caring for elderly patients. On her new doctor's website, it says that the mean systolic blood pressure among elderly females is 120 millimeters of mercury (mmHg). Charmaine believes the value is actually higher. She bases her belief on a recently reported study of 10 randomly selected, elderly females. The sample mean systolic blood pressure was 128 mmHg, and the sample standard deviation was 25 mmHg. Assume that the systolic blood pressures of elderly females are approximately normally distributed. Based on the study, at the 0.10 level of significance, can it be concluded that u, the population mean systolic blood pressure among elderly females, is greater than 120 mmHg? Perform a one-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places. (If necessary, consult a list of formulas.) (a) State the null hypothesis H, and the alternative hypothesis H,. Ho :0 H,…

Suppose you've just been hired as a statistics professor, but you've never taught undergrads before. While you're doing your best, you're not sure you're fully up to par with all the other excellent statistics professors out there. You decide to look at your 41 students' grades on their midterm exam. They averaged grades of 81 on this exam, with a standard deviation of 10. You reason that if they're higher than normal, you might be making things too easy for them. Likewise, if they're lower than normal, you might be making things too hard. Seeking a Goldilocks effect, you compare this with the national average of statistics midterm exam scores - this is 79.  BEING SPECIFIC, what kind of statistical analysis should you perform, and WHY? Three parts of your answer will factor into the grade on this answer: the type of statistical test, one specific aspect of this test (hint- see the earlier questions), and your explanation as to why.

According to the College Board, scores on the math section of the SAT Reasoning college entrance test for the class of 2010 had a mean of 516 and a standard deviation of 116. Assume that they are roughly normal.One of the quartiles of the scores from the math section of the SAT Reasoning test is 438. The other quartile is _______.